JPH01108690A - Three-dimensional surgical operation simulation device - Google Patents

Abstract

PURPOSE:To freely display a surgical operation model by converting separately an image in a separation range in a binary image and an image outside of the separation range to three-dimensional images, and superposing and displaying them. CONSTITUTION:By designating a separation range, an address generating part 4 fetches only a coordinate value being within its range, and stores it in a memory 5 so as to correspond to the slice surface. As a result, in a memory 3, only the separation range is eliminated and only the image of a non- separation part is left. Subsequently, a three-dimensional image generating device 6 obtains a three-dimensional image from the image of the memory 3 and stores it in a memory 7, thereafter, obtains a three-dimensional image from the image of the memory 5 and stores it in a memory 8. In such a way, a superposition processing part 9 executes superposition of the images of the memory 7 and 8, and a CRT 10 displays its three-dimensional image which is processed. As for the superposition processing, when the images of the three- dimensional image memory 8 and 7 are superposed, it will suffice that the contents of the memory 8 are processed preferentially, and this side is processed preferentially, comparing with the rear.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a three-dimensional surgical simulation device.

[Conventional technology]

In conventional plastic surgery, etc., a surgical model was created using a piece of paper, and the surgery was performed according to this model.

Instead of a surgical model using a piece of paper, a surgical model based on an electronic three-dimensional image is also considered, and the applicant has already filed a patent application (width 11 eyebrows L sides μ) 7).

Conventional examples of 3D image creation include ``3D processing of computerized tomographic images'' (Ministry of Education, Culture, Sports, Science and Technology Grants-in-Aid for Fiscal 1985, Results Report, P. of the Proceedings published in March 1985);
28-P, 35゜Principal Investigator, Koji Miyake).

[Problem 3 to be solved by the invention Creating a surgical model using pieces of paper is a very time-consuming task. Furthermore, it is often necessary to create a large number of surgical models, which takes up a lot of work time.

With the development of software, three-dimensional surgical models using electronic images can be displayed freely, and there are great expectations for their use in diagnosis, treatment, and surgery.

The purpose of the present invention is to provide a three-dimensional surgical simulation in which a three-dimensional image is independently obtained by instructing only the necessary parts such as molding when creating a surgical model using electronic images.

The purpose of this project is to provide a

[Means for solving problems]

The present invention provides two methods corresponding to specified absorption values extracted from CT tomographic images.
A first memory that stores a value image, a second memory that stores a binary image in a designated separation range in the first memory, and a binary image other than the separation range in the first memory. 3
creating means for creating a three-dimensional image from the binary image within the separation range in the second memory; means for superimposing the two three-dimensional images; It consists of a display device that displays superimposed three-dimensional images.

[Effect]

According to the present invention, an image within the separation range and an image outside the separation range in a binary image are separately converted into three-dimensional images, and the images are superimposed and displayed.

[Embodiment] FIG. 1 shows an embodiment of a three-dimensional display device of the present invention. This embodiment includes a CT tomographic image memory 1, a coordinate value extraction unit 2.2, a binary memory 3, an address creation unit 4, and a separation binary memory 5.3.
The dimensional image creation device 6 consists of a three-dimensional image memory 7.8, a superposition processing section 9, and a CRT (display) 10.

CT tomographic image memory: CT tomographic images #1 to #n of n tomographic slice planes of the subject are stored. Each CT tomographic image is an X-ray absorption distribution on its slice plane. The interval between adjacent slice planes is approximately several IIm.

Coordinate value extraction unit 2: By specifying an absorption value range from the outside, absorption values within the range are read out for each slice plane of the memory 1 to obtain a binary image. The manner in which this binary image is obtained will be explained with reference to FIGS. 2 to 4. FIG. 2 shows the relationship between subject tissue constituents and X-ray absorption values. The absorption value shall take a value between 0 and 1000. At this time, it is known that bones have an absorption value of several hundreds, and skin has an absorption value of several tens. In addition to this, absorption values are taken depending on the tissue structure. In addition, to obtain the 07 image, the absorption value at each point of the CT tomogram (absorption on the slice plane = 3-value distribution) is converted into a tissue construct based on the relationship shown in Figure 2, and this is If you display it, you will get 07 image. Since obtaining this 07 image is not directly related to the present invention, further detailed description will be omitted.

In this example, the absorption value range (for example, the lower limit 1
00 to upper limit value 1000), and only absorption values within that range are retrieved from the memory 1 for each slice plane. The retrieved contents are (#i, x, y, γ). Here, #i
is the slice plane number (position in two directions), X and y are coordinates within the slice plane, and γ is an absorption value of 100 to 1000.

This extraction value (#i, x.

y, r), the absorption value γ takes various values from 100 to 1000, but it is assumed that γ=“1” regardless of the magnitude of this value. As a result, the retrieved value is (#i, x.

y), resulting in a so-called binary image. 100-1
This is because absorption values other than 000 are set to "0".

This binary image is a set of coordinates that are r-1, and may be called a coordinate value image. This eliminates the need to store up to the γ-0 range, and the memory capacity (memory 3.5)
can be drastically reduced.

FIG. 3 shows an example in which an absorption value range is specified and only a specific tissue (for example, a bone image) is extracted. FIG. 4 shows an example of a binary image in which the position where only the bone image exists is set to "1" and the other positions are set to "0". If only the "1" portion in the bone image is indicated by coordinates in this binary image, a coordinate value image is obtained.

Binary memory 3: The binary memory 3 stores a binary image (coordinate value image, hereinafter the same) of a designated absorption value range extracted for each slice plane.

Address generation unit 4, separation binary memory 5...The surgical site is specified as a separation range from the outside, and the address generation unit 4 converts this separation range into an address in the memory 3 and accesses the memory 3. do. As a result, 2
(Only the i image is separated, and the separated binary image is stored in the memory 5. Note that the binary image to be separated remains in the memory 3 as it is.

Three-dimensional image creation device 6...Creates a three-dimensional image from a binary image. A three-dimensional image is a pseudo three-dimensional image created by processing such that distant areas are darkened and nearby areas are brightened.

=6- The production device 6 is detailed in the above-mentioned literature. Note that when referring to a three-dimensional creation device, component 2. 3. 5 (or 6)
It is often called including. According to this nomenclature, the creation device 6 may be called a creation device main body. This three-dimensional creation device 6 first uses the binary image in the memory 3 to obtain a three-dimensional image, and then uses the binary image in the memory 5 to obtain a three-dimensional image.

Three-dimensional image memory 7: Stores the created three-dimensional image outside the separation range in the memory 3.

Three-dimensional image memory 8: Stores the created three-dimensional image within the separation range in the memory 5.

Superposition processing section 9: Three-dimensional images in memories 7 and 8 are superimposed on each other. The overlapping portion becomes a double image, making it difficult to see the separated image itself. Therefore, the superimposition processing unit 9 processes the separated portions that have been duplicated so that only the three-dimensional image after separation is displayed. Furthermore, only the three-dimensional image of the separated portion is often shifted and used for observation or for diagnosis for surgery. In this case, we would like to process the double image caused by the positional shift so that only the separated part is visible. This process is also performed by the superposition processing unit 9.
will do. This process may also be called superposition process.

The overlapping of double images will be explained with reference to FIG.

The bone image in FIG. 5(a) is a binarized image on one slice plane that has already been binarized. Such a binarized image #1
Assuming that a 3D image is obtained from ~#n, the lower part of this binarized image is the image in front of the display and is displayed brightly, and the upper part is the image behind the display and is displayed darkly. be done. However, when a separated portion is designated as indicated by a dotted line, the bone image shown in FIG. 5(a) is divided into a separated binary image and an image to be separated, and each is subjected to three-dimensional processing separately. As a result of this processing, the binary image to be separated becomes a three-dimensional image with the separated portion still missing. However, the depth portion indicated by diagonal lines remains as is. Therefore, when converted into a three-dimensional image, the diagonally shaded portions of the separated binarized image (three-dimensional) A and the binarized image to be separated (three-dimensional) B overlap. This overlapping makes it difficult to see only image B alone. Therefore, it is necessary to prevent the deep part of such an overlapping part from being displayed. This processing is superposition processing.

CRTIO: Captures and displays a three-dimensional image after superposition processing.

The entire operation shown in FIG. 1 will be explained.

The CT tomographic image memory 1 stores CT tomographic images for each of n slice planes. An access address is given to this memory 1, and tomographic images of slice planes are read out in the order of #1→#2→...→#n. The coordinate value extraction unit 2 selects only the absorption values in the absorption value range specified from the outside for the CT tomogram for each slice plane to obtain (#i, x, y, γ), and then aligns them with γ-1. and binarized image (#i, x, y
).

The binarized image (#f, x, y) is compiled for each slice plane and stored in the memory 3.

By specifying the separation range, the address generation unit 4 extracts only the coordinate values within the range and stores them in the memory 5 corresponding to the slice plane. As a result, only the separated range is removed and only the image of the non-separated portion remains in the memory 3.

Next, the three-dimensional image creation device 6 generates a three-dimensional image from the image in the memory 3.
A dimensional image is obtained and stored in the memory 7, and then a 3-dimensional image is obtained from the image in the memory 5 and stored in the memory 8. The superposition processing unit 9 superposes the images in the memories 7 and 8, and the CRTIO displays the processed three-dimensional image.

In the superimposition process, when the images in the three-dimensional image memory 8 and the memory 7 overlap, the contents of the memory 8 are given priority, and the front side is given priority over the rear side.

FIG. 6 shows an example of specifying the separation range. A three-dimensional image is displayed, and the operator, looking at this image, indicates the separation range (the rectangle indicated by the dotted line) using a trunk ball, a mouse, or the like. The contents of this instruction are read and set as the designated separation range for the address creation section 4.

In this case, the initially displayed three-dimensional image is a three-dimensional image based on the image in the memory 3 before data is projected onto the separation memory 5.

According to this embodiment, it is now possible to create a surgical model on a pseudo-I three-dimensional image obtained from an XCT tomographic image. Note that examples of ultrasonic CT and MR-CT are also possible.

Furthermore, since the image of the separation range is a single image, it may be difficult to move,
It can be handled as a target for processing such as rotation deletion.

This makes it possible to visualize various surgical models. Note that processing such as movement and rotation may be performed within the device 6, or may be performed by a processing section provided between the device 6 and the memory 5.

Furthermore, although the creation device 6 created the two three-dimensional images serially, it is also possible to process them in parallel.

〔Effect of the invention〕

According to the present invention, it has become possible to create a surgical model using an electronic image model. In particular, since parts such as removal and molding can be handled separately, surgical models can now be displayed more freely.

[Brief explanation of the drawing]

Fig. 1 is an embodiment of the present invention, Figs. 2 to 4 are explanatory diagrams for obtaining the 2 It is a diagram showing an example. 1... CT tomographic image memory, 3... Binary memory for specified absorption, 5... Separation memory. Patent applicant: Hitachi Medical Co., Ltd. Agent Patent attorney: Masami Akimoto ( 1 other person) 3y!, original picture 4
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Claims (1)

[Claims] 1. A first memory that stores a binary image corresponding to a designated absorption value extracted from a CT tomographic image, and a second memory that stores a binary image of a designated separation range separated from the first memory; means for creating a three-dimensional image from a binary image outside the separation range in the first memory, and creating a three-dimensional image from a binary image within the separation range in the second memory; A three-dimensional surgery simulation device comprising means for superimposing three-dimensional images, and a display for displaying the superimposed three-dimensional images after the processing.